WOOTOK AlTD STaNDL£1* — FLORA OF NEW MEXICO. 409 



KEY TO THE SPECIES. 



Leaves evergreen, thick; flowers axillary in small clusters; wood 



of stems very hard 1. R, choriophylla. 



Leaves deciduous, tliin; flowers in dense terminal panicles; wood 

 of stems soft, with large pith. 

 Rachis winged; leaflets densely pubescent beneath, of the 



same color on both surfaces 2. R. lanceolata. 



Rachis not winged; leaflets glabrous and paler beneath 3. R. cismontana. 



1. Rhus choriophyUa Woot. & Standi. Contr. U. S. Nat. Herb. 16: 146. 1913. 

 Type locality: Guadalupe Canyon, New Mexico. Type collected by E. A. 



Mearns (no. 699). 



Range: Southern New Mexico and Ai'izona and adjacent Mexico. 



New Mexico: Guadalupe Canyon; San Andreas Mountains; Organ Mountains. 

 Dry hills and canyons, in the Upper Sonoran Zone. 



2. Rhus lanceolata (A. Gray) Britton in Britt. & Shaf. N. Amer. Trees 606. 1908. 

 Rhus copallina lanceolata A. Gray, Bost. Journ. Nat. Hist. 6: 158. 1850. 

 Schmaltzia lanceolata Small, Fl. Southeast. U. S. 728. 1903. 



Type locality: Rocky soil and high praii'ies. New Braunfels, Texas. 

 Range: Central Texas to southeastern New Mexico. 

 New Mexico: Queen; San Andreas Mountains. Dry hills and canyons. 

 Our specimens are not altogether typical, the pubescence being more abundant 

 and spreading than is usual, while the leaflets are smaller and the inflorescence shorter. 



3. Rhus cismontana Greene, Proc. Washington Acad. Sci. 8: 189. 1906. 

 Rhus sorbifolia Greene, op. cit. 195. 1906. 



Type locality: Thomas County, Nebraska. 



Range: Utah and North Dakota to New Mexico and Arizona. 



New Mexico: Sandia Mountains; mountains west of Las Vegas; Kingston; Mogo- 

 llon Creek; Guadalupe Canyon; \^niite Mountains. Along streams, in the Transition 

 Zone. 



The type of Rhus sorbifolia was collected in the mountains near Las Vegas. 



84. CELASTRACEAE. Staff-tree Family. 



Low shi'ubs, sometimes spiny; leaves simple, small, alternate or opposite; flowers 

 normally cyraose, small and inconspicuous, perfect; calyx and corolla 4 or 5-merous; 

 stamens 4 to 10, inserted on a disk lining the hypantliium; fruit a capsule, drupe, 

 or berry, the seeds often arillate. 



key to the genera. 



Stamens 10; plants spiny; stems green 1. Forsellesia (p. 409). 



Stamens 4 or 5; plants not spiny; stems yellowish or 

 brown. 

 Flowers 4-merous; fruit a 2-valved capsule; leaves 



opposite, smooth 2. Pachistima (p. 410). 



Flowers 5-merous; fruit indehiscent; leaves alternate, 



scurfy 3. Mortonia (p. 410). 



1. FORSELLESIA Greene. 



A spiny green-stemmed shrub 30 to 40 cm. high or less, with small obovate acute 

 leaves 1 cm. long or smaller, these nearly smooth, short-petioled, entire; flowers small, 

 pentamerous, white. » 



